Omni F550 Fuel Usage

[droregon]

Update:

RV has been in Ford Truck Service Center since December 20. Delays in service due to weather & staffing. Can’t figure out the problem. Never seen or heard of this problem. Shop is in contact with Ford Truck Tech Support, Detroit. It might be computer/electronics???… More to come.

 

[droregon]

Picked it up from Ford Truck Service Center. They had it a month due to weather & COVID short staffing. Problem still not solved. They think it’s a pinched fuel line. Computer detects fault low fuel flow from rear tank. Can’t see any under carriage damage to tanks or lines, but line tracing view hampered by motorhome box. (?!?) I’m heading to Arizona for Spring Training and have appointment in late April to bring it back into shop. Hopefully, they’ll be back to full staffing by then. Will have to continue to operate with reduced useable fuel capacity. Shop believes next step is to remove fuel tanks to fully examine tanks & lines… Not Happy

 

[droregon]

Update: After spring in Arizona, returned RV to Ford Truck Service Center on April 22, 2022. Delays in servicing again. Verified problem again. Removed fuel tanks for inspections. No damage to tanks and lines. No restrictions to lines. Suspect Main Tank Pump failure. Replaced Main Tank Pump. Idle and road test confirms fuel transfer. Believe problem solved. Picked up RV July 29, 2022. Drove Portland to Redmond (110 miles) after pickup. Suspect problem not solved, but need longer road test.

Update: Just returned from RV Trip. Redmond OR to Whidbey Island WA, 800 miles round-trip. Problem definitely not solved. Started trip with both tanks full. After several front tank refills when down to 1/4 tank, rear tank remains at 3/4. So, I get some pull from rear tank, but not what it should be. Will contact Service Center tomorrow to schedule next steps.

 

[Judge64]

Update: After spring in Arizona, returned RV to Ford Truck Service Center on April 22, 2022. Delays in servicing again. Verified problem again. Removed fuel tanks for inspections. No damage to tanks and lines. No restrictions to lines. Suspect Main Tank Pump failure. Replaced Main Tank Pump. Idle and road test confirms fuel transfer. Believe problem solved. Picked up RV July 29, 2022. Drove Portland to Redmond (110 miles) after pickup. Suspect problem not solved, but need longer road test.



Update: Just returned from RV Trip. Redmond OR to Whidbey Island WA, 800 miles round-trip. Problem definitely not solved. Started trip with both tanks full. After several front tank refills when down to 1/4 tank, rear tank remains at 3/4. So, I get some pull from rear tank, but not what it should be. Will contact Service Center tomorrow to schedule next steps.

Definitely an odd problem......



My tanks are like clockwork. Once my front tank hits 3/4 full, the rear tank starts to siphon over until its about empty and then then rest of the front tank empties.



I do notice that if I park the coach for a while with the rear tank full and the front tank at 3/4 full, the tanks will balance as some of the rear tank siphons over to the front tank. The gauges will read like 7/8 front and rear after sitting.

 

[RobintheHood]

Update: After spring in Arizona, returned RV to Ford Truck Service Center on April 22, 2022. Delays in servicing again. Verified problem again. Removed fuel tanks for inspections. No damage to tanks and lines. No restrictions to lines. Suspect Main Tank Pump failure. Replaced Main Tank Pump. Idle and road test confirms fuel transfer. Believe problem solved. Picked up RV July 29, 2022. Drove Portland to Redmond (110 miles) after pickup. Suspect problem not solved, but need longer road test.

Update: Just returned from RV Trip. Redmond OR to Whidbey Island WA, 800 miles round-trip. Problem definitely not solved. Started trip with both tanks full. After several front tank refills when down to 1/4 tank, rear tank remains at 3/4. So, I get some pull from rear tank, but not what it should be. Will contact Service Center tomorrow to schedule next steps.

I wonder if the rear tank vent is restricted...

 

[droregon]

Update: Problem Solved.

I've been remiss for not posting earlier. Been out & about.

After my Whidbey trip, returned the RV into the Ford Truck Service Center on Aug 30, 2022. They worked on it until Oct 14, 2022, in contact with Ford Hot Line Assistance.
After removing rear tank and replaced sending pump, reinstalled tank. They ran it idle to monitor gauges. All seems ok.

I picked up RV on Oct 14 and drove home (Portland to Redmond, OR, 110 miles). Seems ok. Then I winterized unit.

De-winterized unit on Feb 6, 2023 and headed south again to Arizona. Yeah! It's really working! It's great to have a 600 mile range vs. only 200 miles.

So, in summary, after three visits to the shop with Ford Hot Line Assistance, pulling both tanks to inspect lines for pinches or breaks (none found) and testing vents, they replaced both pumps (front pump pulls, rear pump sends), and now everything works as advertised.

Thank you Ford Trucks. No cost to me (other than inconvenience and cost of three trips back and forth from Portland to Redmond).

 

[Pillboxmc]

Thanks for the follow up.